The present invention relates to a linear roller bearing element.
Linear roller bearing elements of this type are used for linear roller bearing guides, with which the roller bearing elements are located between a guide rail and a guide carriage supported on the guide rail such that it is displaceable relative thereto. Roller bearing guides of this type are known and are available in diverse configurations. They are composed of a solid guide carriage, which may be moved via the rolling elements on the guide rail, relative to the guide rail. Systems are used that are known with regard for roller bearings. The profile of the raceway has a gothic shape, or it approximates the segment of a circular arc. Systems having four rows, six rows, or an even greater number of rows are known. Since the guide rail and the guide carriage are composed of solid metal—steel, in particular—a deformation takes place when force is applied off-center, i.e., when loads are applied obliquely, when torque is applied, or the like.
The deformation results in different deflections of the spherical rolling elements and uneven deformations of the carrier body. With low-profile, narrow guide carriage bodies, which have a small cross section and therefore have only a small amount of support material available, this therefore results in uneven running and negative effects on the service life. If, e.g., torque loads are applied around the rail longitudinal axis, the outwardly lying guide raceways are stressed heavily, while the inwardly lying guide raceways are less involved in the load transfer. The points of contact are displaced significantly. To account for this, the raceways of the guide rail must be ground very deep. This is very costly. In addition, the contact surfaces may only be used to a limited extent, so the dimensions of the roller bearing guide must be increased, or its maximum loading capacity must be reduced, to prevent the running behavior from becoming seriously impaired.
Linear roller bearing elements have become known, with which, in terms of the support in the guide carriage, the carrier body is self-adjusting in a swiveling manner around a longitudinal axis. To this end, the carrier body includes a partially cylindrical outer surface, which is accommodated in an assigned, appropriately shaped groove of the guide carriage. The disadvantage of this is that the carrier bodies may become displaced relative to the return of the rolling elements, which takes place in the guide carriage. This results in poorer-quality running, increased noise development, and a relatively high load on the rolling elements.